lobes: narrow, sublinear to subirregular, contiguous to imbricate, elongate, plane, separate, 7-13 mm wide; tips: rotund, sparsely to moderately ciliate; cilia: simple, black, up to 4 mm long upper surface: mineral gray (but turning buff in herbarium), smooth but cracked with age, shiny, becoming rimose, strongly effigurate maculate, becoming rugose isidia: cylindrical, simple to coralloid branched, laminal, rarely ciliate apically; soredia and pustulae absent medulla: white lower surface: pale brown to dark brown in center, densely rhizinate, rhizines black, simple Apothecia: rare, 3-8 mm diam.; margin: isidiate; disc: imperforate when young asci: clavate, 8-spored ascospores: ellipsoid, 8-11 x 5-8 um Pycnidia: laminal, immersed conidia: cylindrical-fusiform, 4-7 x 1 micro meter Spot tests: cortex K+ yellow, C-, KC-, P+ yellow; medulla K+ yellow turning dark red, C-, KC-, P+ orange Secondary metabolites: upper cortex with atranorin and chloroatranorin (both major) and usnic acid (accessory); medulla with salazinic acid (major), consalazinic acid and norlobaridone (both minor) and protolichesterinic acid (accessory). Substrate and ecology: frequent on bark in woodlands, rare on rock World distribution: pantropical and into adjacent temperate regions; North America, Europe, Asia and Australasia Sonoran distribution: common on boulders and canyon walls in mid-montane habitats from SE Arizona south through the Sierra Madre Occidental in Chihuahua, Sonora and Sinaloa and in the mountains of southern Baja California Sur. Notes: The chemistry profile basically corresponds to Hale's (1977) interpretation for the species (e.g. see discussion under Parmotrema neotropicum, p. 438). Earlier reports (Hale 1965) of cryptochlorophaic acid was a misidentification of norlobaridone.